Which of the following is not true about nonnative species? a. they can have positive impacts on an ecosystem. b. they can have negative impacts on an ecosystem. c. they can be introduced within their natural range. d. a nonnative species can be an invasive species.

Natural selection acts on populations through a specific trait. which statement must be true about that trait? question 6 options: the trait is passed on genetically to the next generation. the trait has little impact on survival. the trait is the same for all organisms. the trait is resistant to mutations.

Researchers randomly divide participants into groups. each group takes a different amount of omega-3 fatty acid supplements daily for a month. one group receives a placebo. the researchers measure the impact on cholesterol levels in the blood. what is the purpose of random assignment in this experiment? a, to produce treatment groups with similar characteristics b, to ensure that all people with high cholesterol have an equal chance of being selected for the study c, to increase the accuracy of the research results and prevent skewness in the data

Which sentence is an example of a strong conclusion to an autobiography? a. i stayed after school three days in a row to practice onstage in the auditorium. b. i knew i would have to practice all week to memorize my dance for the recital. c. after the recital was over, i knew practicing was worth it, and i was looking forward to my next big challenge. d. on opening night, i danced in front of a packed auditorium.